The use in diverse applications of bar codes (one-dimensional, such as UPC, Code 39, Code 128; two-dimensional, such as PDF 417, Code 49, Code 16K; etc.), matrix codes (Data Code, Code 1, Vericode, MaxiCode, etc.) and graphic codes (Glyph, etc.) which may be printed or etched on paper, plastic cards and metallic and other items is well known. In addition to such optically machine readable graphics, data is commonly recorded in other machine readable forms, such as optically via invisible ink bar codes or matrix codes and magnetically via magnetic stripes or magnetic ink MICR fonts, on credit cards, checks and identification badges. Similarly, data is recorded electromagnetically via RF tags in a growing variety of forms and applications. In addition to printing, etching and magnetic recording, other methods of forming or transferring dataforms include engraving, ion doping (for semiconductor wafers), stamping, tattooing (for skin), biochemical binding, etc. For present purposes, all arrangements whereby data in some form adapted to be machine readable is fixed in a copy are termed "dataforms".
In present usage, the encoding process for dataforms is carried out in what may be termed a "batch mode". That is, users key-in or otherwise enter the data as a first step and then send or transmit the data to an encoder to be encoded in a machine readable dataform. As a result, the user has no advance knowledge as to important characteristics of the presentation of the actual data in the dataform. Thus, the user or operator of the encoding equipment does not know whether all the data can be encompassed within the dataform in point, and is not aware in advance of the overall appropriateness of inclusion of the data into the required format in a single dataform, or whether use of two or more dataforms would be more appropriate for the best presentation of the particular data at hand. Also the operator is unable to evaluate factors such as final dataform dimensions and resolution, data format and error correction level most appropriate for the dataform being coded. As a result, the user is left to the approach of entering and encoding data and examining the resulting coded dataform. A further trial and error approach may then be necessary in order to arrive at an optimal or acceptable encoding format. For the next different batch of data the same trial and error approach must be followed even if the coded dataforms are being output in a printed or similar visually observable form. Of course, if the output datacodes are encoded in a magnetic, invisible ink or other medium in a non-visual format it is even more difficult for the operator to monitor the encoding process to determine the encoding parameters appropriate for optimal, or even merely acceptable, dataform coding and presentation.
On the decoding side, prior decoding systems (using a hand-held scanner, for example) are dependent on the user placing the scanner with an appropriate positioning and spacing from the dataform to be decoded (a bar code, for example). However, there is typically no provision for permitting confirmation of positioning or spacing. As a result, the bar code may be only partially within the scanner field of view, may be significantly off center or out of focus, or may be too far away from the scanner, any of which may result in a small or otherwise inadequate image causing reduced accuracy of reading, or partial or complete failure to read the dataform. Again, a trial and error approach may be necessary to accomplish accurate reading of the dataform after one or more repeated attempts, particularly where magnetic, invisible ink or other non-visual formats are involved.
As examples of prior patents which describe encoding and decoding systems (but which do not provide visually interactive methods or systems so as to avoid the potential need for trial and error repetition) attention is directed to the following. U.S. Pat. Nos. 5,113,445 and 5,243,655 cover two-dimensional bar code encoding and decoding inventions of a present applicant. Earlier U.S. Pat. No. 4,939,354 covers production and reading of two-dimensional data code machine readable matrices.
Objects of the present invention are, therefore, to provide new and improved systems and methods for decoding machine readable dataforms which avoid one or more disadvantages of prior such systems and methods, and to provide dataform decoding systems and methods providing benefits of visual or automated interaction during decoding.